Was able to achieve it this way
app.use('/api', function (req, res) { let url = config.API_HOST + req.ur req.headers['someHeader'] = 'someValue' req.pipe(request(url)).pipe(res) })
for some weird reasons req.setHeader('someHeader', 'somValue') didn't work for me.
req.setHeader('someHeader', 'somValue')
but req.headers['someHeader'] = 'someValue' this worked
req.headers['someHeader'] = 'someValue'